Ok, thank you
This works, but now I have 2 burger menu icons, which are overlapping the logo. That’s not, what I wanted. Is ist possible to set the sticky header under the 2nd menu line?

Can I upload Images to demonstrate?

Hi Rikard,
thank you for your response.
My Web-Host said, that I have already much memory space. I think, that it is possible that the problem is coming from the widget.
Kind regards, Sandra